ForeignKey foreignKey default @ForeignKey(ConstraintMode.PROVIDER_DEFAULT)

(Optional) Used to specify or control the generation of a foreign key constraint for the columns corresponding to the JoinTable.joinColumns element when table generation is in effect. If both this element and the foreignKey element of any of the JoinTable.joinColumns elements are specified, the behavior is undefined. If no foreign key annotation element is specified in either location, a default foreign key strategy is selected by the persistence provider.